Pipe inspecting apparatus



INVENToR.

/QOQA/EPS ,9940/9 M CI/EL,

BY Y

R. K. CADWELL PIPE INSPECTING APPARATUS Filed Nov. l, 1949 Sept. 9, 1952Patented Sept. 9, v1952 UNITED- ySTATES TENT N OFFICE .2 claims. 1 Thisinvention relates to a pipe inspecting apparatus. I .I

In the manufacture of pipe as well as the assembly of sections thereof,welding 'is frequently employed to weld `not only longitudinal seams butcircumferential seams.` It is desirable to inspect the pipe from theYinterior to determine whether or not any defects or defective welds arepresent. Thisis particularly true where 'the pipe is of such small sizethat it is impossible for a man to enter the pipe and make a directinspection.

An object of the present invention `is to provide a simple apparatusthat canbe readily inserted into a pipe and whichV will enable either orboth the lcngitudinaland circumferentialseams to be inspected, and`which will enable a defect to be accurately located on the exterior ofthe pipe so that correction may be made at such point `or points withoutdisturbing in any way the remainder of the pipe. ,l Y

With the foregoing and other objects in View, which will be mademanifest in the iollowingdetailed description and specificallypointed'out in the appended claims, referenceis had to the accompanyingdrawings for an illustrative embodiment of the invention wherein:

`Figure 1 is a sectorial view through a pipe to be inspected andillustrating the inspection apparatus embodying the present invention asdisposed therein;

Fig. 2 is a sectional view taken substantially upon the line 2-2 uponFig. 1; and

Fig. 3 is a sectional View taken substantially upon the line 3--3 uponFig. 2.

Referring to the accompanying drawings wherein similar referencecharacters designate similar parts throughout, the pipe to be inspectedis indicated at P which may have a longitudinal seam, not shown, and/orcircumferential seam S which has been welded and which it is desired toinspect :from the interior of the pipe.

The inspection apparatus embodying the present invention consists of atube generally indicated at IB which may be made up of assemblablesections of tubing that are assembled together and held rigidly in endto end relationship by clamps I I which are tightened by means of boltsI2. The number of sections of tubing employed may vary and likewisetheir lengths may vary depending upon the location of thecircumferential seam S from the end of the pipe through which access maybe gained. On the endmost sections of the tubing IB there are shouldersi3 and I4 against which supports for the tube can be removablypositioned. Each support consists ithe center of the pipe.

`support to the interior of the pipe is not essential y `2. of a collarI5 within which there is an `antiiriction bearing I6. This anti-frictionbearing may be a ball bearing but preferably is a needle bearingenabling the tube I0 to rotate freely within its supports. Each collarI5 is retained against its shoulder by means of a ring Il carrying `aset screw I8 that can betightened against the tubing. On loosening theset screw the ring I 'I can be slipped oli of the tube and the supportsremoved therefromin transporting the apparatus Vfrom place to place.

`On the outer side of the collars I5 there are sockets I9 for thereception of pipe nipples 20 and casters 2| are mounted on the outerends of these nipples. The nipples 2l) are replaceable by other nipplesof different lengths so that the radial distance of the casters 2l fromthe axis of the tubing I9 can bev adjusted. 'The casters are lad'-justed radially from the axis of the tubing I0 sc that they willapproximately iit the interiorof the pipe P and hold the tubing I Datgsub'stantially An exact erung f the as reasonably satisfactoryresults can be obtained even thoughthc` tubing In is not concentricallyarranged with relation to the pipe.

At one end of the tubing there is disposed a mirror or equivalent lightreecting means 22. This mirror is so arranged as to receive light froma` point 23 that is radially arranged with relation tothe tubingl andwhich may be on the interior cf the seam S and reflect such lightlongitudinally of the tubing. A lamp `2li is mounted onthe end of thetubing and is focused to project light on and in the vicinity oi thepoint 23. This lamp can be an electric lamp supplied with current toconductors 25 from any suitable source.

Y rihe mirror 22 may be protected by a lens 25.

At the other end of the tubing I0 an angular telescope 21 is rotatablymounted on the tubing. This telescope has an angularly disposed eyepiece23 and is adjustable to have a focal length equal to the length of thepipe that is to be inspected. The telescope is focused on the mirror 22so that by looking into the eyepiece 28 the tester can visuallyascertain the condition of the Weld at the point 23. An indicator 29 isclamped by means oi a clamp 30 on the tubing and may serve as a meansfor rotating the tubing IIl to direct the mirror 22 to various pointsaround the interior of the circumferential seam. The indicator 29 isclamped on the tubing IIJ so as to be in direct longitudinal alignmentwith the point 2t. Consequently, by rotating the tubing by 'neansoi theindicator 2i! if a defect is located 3 anywhere on the circumferentialseam S the in dicator will indicate its location on the circumference ofthe seam.

Preferably the indicator 29 is clamped on the tubing l at such aposition that its point will be either in direct radial alignment withor in engagement with the edge of the pipe surrounding the openingthrough which the instrument is inserted. When the indicator is thusclamped on the tube it may serve not only as a means for rotating thetubing lil within its support, but it will also serve to maintain themirror 22 and the lamp 24 focused on the circumferential seam that isbeing inspected. In other words, by maintaining the indicator 29 in'engagement with the end edge of the pipe the mirrorand its lamp can bekept from wandering from the circumferential seam in the course ofinspection. Y

In inspecting longitudinal seams, the indicator 29 is clamped on thetubing I0 in such a position so as to be spaced a definite or knowndistance from the point 23 on which the lamp 24 and the mirror 22 varefocused. Thetubing is then slowly introduced intothe pipe and heldagainst rotation by the indicator 29, causing the point 23 to slowlyprogress along the longitudinal seam. If a defect in the longitudinalseam is observed its location can be marked by measuring on the exteriorof the pipe the predetermined or known distance between the indicatorand the point 23. This distance is laid olf from the indicator 29 on theexterior of the pipe and corrective measures are taken to correct thedefect. The indicator 29 may thus serve to perform several functionsincluding a means for rotating the tubing I9 to cause the point 23 Atoprogress around a circumferential seam to indicate the position of adefect on a circumferential seam after it has been observed through thetelescope and to serve as a reference point from Y which the location ofa defect on a longitudinalseam can be measured. As above explained, whenvthe indicator is in engagement with the edge of the pipe it also servesas a guide 4for keeping. the lamp and mirror focused on thecircumferential seam when a circumferential seam is inspected.

, It will be appreciated from the above described construction that theimproved inspection apparatus will enable the longitudinal andcircumferential seams in pipes to be easily inspected and cumferentialseam as the telescope is not rotated with the tubing, it is quite easyto look downwardly into the telescope in all positions of the tubing inthe course of making an inspection. Although the telescope remainsstationary to facilitate looking into the telescope when a defect isobserved its location can be easily determined accurately from theposition of the indicator 29.

Various changes may be made in the details of construction withoutdeparting from the spirit and scope of the invention as dened by theappended claims.

I claim:

l. A pipe inspecting apparatus comprising a tube, supports for the tubefor supporting the same within a pipe, said supports having castersadjustably mounted at circumferentially spaced points thereon,anti-friction bearings between the tube and said supports, a mirror onone end of the tube arranged to receive light from a point radially withrespect tothe tube, means for projecting light on said point, atelescope rotatably mounted on the other end of said tube, and anindicator on the tube in longitudinal alignment with said point. l

2. A pipe inspecting apparatus comprising a tube made up of sectionsclamped in longitudinal alignment, supports rotatably mounted upon saidtube, said supports having radially adjustable casters thereon adaptedto engage the interior of a pipe to be inspected, a mirror at one end ofthe tube adapted to receive light from a point radially of the tube, alamp mounted on the tube focused to project light in the vicinity ofsaid point, a telescope having an angularly disposed eyepiece rotatablymounted on the other end of the tube, and an indicator clamped upon thetube adjacent the telescope in longitudinal alignment with said point.

RALPH K. CADWELL.

REFERENCES CITED The following references are of record in the file ofthis patent:

Great Britain Feb. 12, 1912

